Do you mean harder cos she will attack me or harder cos they don't wanna sit on them when moved?
Maybe both... ducks tend to be more aggressive about protecting their eggs, it's hit or miss if they let you near... and they are exceptionally picky about their nesting spots... if possible, I would move her nesting material with her as well... that *might* help...
Test out how she reacts first... try approaching her and see how she does...